Study Finds RA Link in the Microbiome

A new study has found a direct link between specific bacteria in the gut and rheumatoid arthritis (RA) -- an exciting discovery that could bring us closer to understanding the cause or causes of RA.

Micro bacteria in the gut

Each of us has a collection of microbacteria in our guts. The collection, which weighs roughly three pounds in an adult, is called the microbiome and is made up of about 1,000 different bacterium species. Microbacteria play an important role in our health: some protect us against illness, while others possibly play a role in the development of certain illnesses.

The new study by researchers at Mayo Clinic investigated the theory of a link between the microbiome and rheumatoid arthritis. They found that rare bacteria become more abundant in people with RA, resulting in a microbial imbalance (also called dysbiosis).

In the study, the 16S ribosomal DNA was sequenced in fecal samples from people with RA and healthy controls. Findings showed that individuals with RA had lower microbial diversity in their gut. This was also correlated with how long individuals had had RA, as well as their autoantibody levels.

Furthermore, the study found that certain microbacteria were abundant compared to the controls. In particular, a bacteria called Collinsella was associated with the production of the IL-17A cytokine, which plays a role in inflammation. According to Dr. John Davis III, co-author of the study, subsequent experiments demonstrated that there was a direct causal link between Collinsella and the arthritis phenotype.

An additional interesting finding in the study relates to the effect of medication on the diversity of the microbiome. The researchers discovered that individuals who were taking methotrexate and hydroxychloroquine showed an increase in the diversity and richness of the microbacteria species. They posit that this could potentially indicate that treatment of RA leads to restoring a more normal state of the microbiome.

In their conclusion, the authors of the study theorized that the microbial imbalance could also be addressed by using probiotics. However, they point out that results of treatment by probiotics for RA are inconclusive: some studies show a beneficial effect, others do not. Clearly, more research is needed in this area.

My take

This is a very exciting development in RA research. I thought the findings of the effects of treatment on the microbiome to be especially interesting in an already very interesting study. This demonstrated that treating RA has wide-reaching implications.

That said, I was a little concerned about the study’s mention of using probiotics to treat RA. It does makes sense — probiotics are known to balance the microbacteria in the gut. Many people use it for that purpose when taking antibiotics, which are known to negatively impact gut health. Others use probiotics to address the effects of RA meds. I do this myself and find it very helpful. Has it had an impact on my RA? I don’t believe so.

What concerns me is the possibility that people who have RA might stop taking their medication and try to treat their RA only with probiotics. Adding probiotics to your health care regimen may be a good idea, so by all means discuss this with your doctor.

However, using probiotics to treat RA without any other medications would, I believe, be premature. Much more research is needed in this area before drawing conclusions about the treatment possibilities of probiotics. In the meantime, using existing RA meds that have been proven to have a beneficial effect on the disease is much more likely to help you control inflammation and the detrimental effects it can have on your health.

We live in a really exciting time for rheumatoid arthritis research. Every year, new developments emerge that bring us closer to understanding the cause of RA. Every new piece of the puzzle has profound impact in terms of the development of effective treatments. I truly believe that we will see a cure in my lifetime.